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1.
Opt Lett ; 49(10): 2689-2692, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748137

RESUMO

To enhance the integration and practical applicability of the Raman detection system, silver nanocubes (Ag NCs) were synthesized using a polyol method. A liquid-liquid interface approach was employed to transfer a monolayer of Ag NCs "film" onto a SiO2 substrate, resulting in the fabrication of a highly sensitive and uniform surface-enhanced Raman scattering (SERS) substrate denoted as "Ag NCs@SiO2." The electromagnetic field distribution of various dimers on the Ag NCs@SiO2 was analyzed using finite difference time domain (FDTD) software. The results reveal that the electromagnetic enhancement effect is most pronounced in cube-cube dimers, indicating that Ag NCs exhibit superior localized surface plasmon resonance (LSPR) response due to their well-defined geometric regularity and sharp geometric angles. For Rhodamine 6G (R6G) probe molecules, the Ag NCs@SiO2 shows ultrahigh sensitivity, with a limit of detection (LOD) of 10-12 mol/L, and the enhancement factor (EF) can reach 1.4 × 1010. The relative standard deviation (RSD) at the main characteristic peaks is below 10%, demonstrating good consistency in substrate performance. In addition, the Ag NCs@SiO2 modified with hexanethiol exhibits high sensitivity, uniformity, and repeatability in detecting for pyrene, with the LOD of 10-8 mol/L and a minimum RSD of 6.09% at the main characteristic peak, and effective recognition capabilities for pyrene and anthracene in mixed solutions. Finally, chemisorption and physisorption strategies were prepared in optofluidic channels and experimentally compared, enabling real-time detection of the pyrene solution. This method can achieve a rapid detection and precise differentiation of polycyclic aromatic hydrocarbons in a water pollutant.

2.
Virol J ; 21(1): 87, 2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641833

RESUMO

BACKGROUND: Bovine parvovirus (BPV) is an autonomous DNA virus with a smaller molecular size and subtle differences in its structural proteins, unlike other animal parvoviruses. More importantly, this virus has the potential to produce visible to silent economic catastrophes in the livestock business, despite receiving very little attention. Parvoviral virus-like particles (VLPs) as vaccines and as logistical platforms for vaccine deployment are well studied. However, no single experimental report on the role of VP1 in the assembly and stability of BPV-VLPs is available. Furthermore, the self-assembly, integrity and stability of the VLPs of recombinant BPV VP2 in comparison to VP1 VP2 Cap proteins using any expression method has not been studied previously. In this study, we experimentally evaluated the self-assembling ability with which BPV virus-like particles (VLPs) could be synthesized from a single structural protein (VP2) and by integrating both VP2 and VP1 amino acid sequences. METHODS: In silico and experimental cloning methods were carried out. His-tagged and without-His-tag VP2 and V1VP2-encoding amino acid sequences were cloned and inserted into pFastbacdual, and insect cell-generated recombinant protein was evaluated by SDS‒PAGE and western blot. Period of infectivity and expression level were determined by IFA. The integrity and stability of the BPV VLPs were evaluated by transmission electron microscopy. The secondary structure of the BPV VLPs from both VP2 and V1VP2 was analyzed by circular dichroism. RESULTS: Our findings show that VP2 alone was equally expressed and purified into detectable proteins, and the stability at different temperatures and pH values was not appreciably different between the two kinds of VLPs. Furthermore, BPV-VP2 VLPs were praised for their greater purity and integrity than BPV-VP1VP2 VLPs, as indicated by SDS‒PAGE. Therefore, our research demonstrates that the function of VP1 has no bearing on the stability or integrity of BPV-VLPs. CONCLUSIONS: In summary, incredible physiochemically stable BPV VP2-derived VLPs have been found to be promising candidates for the development of multivalent vaccines and immunodiagnostic kits against enteric viruses and to carry heterogeneous epitopes for various economically important livestock diseases.


Assuntos
Bocavirus , Parvovirus , Vacinas , Animais , Baculoviridae/genética , Proteínas Recombinantes/genética , Proteínas do Capsídeo/genética
3.
Ideggyogy Sz ; 77(5-6): 161-166, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38829252

RESUMO

Background and purpose:

The aim of this study is to comprehensively determine the types of affected fibers in Parkinson’s disease (PD) patients by employing nerve conduction studies (NCS), sympathetic skin response (SSR) examinations, and current perception threshold (CPT) testing and to analyze the correlation between levodopa use and nerve involvement.

. Methods:

This retrospective study included 36 clinically diagnosed PD patients who were recruited between January 2018 and April 2019. All patients underwent NCS, SSR testing, and CPT sensory examinations. Additionally, the PD patients were assessed for disease staging using the Hoehn and Yahr (H-Y) scale. 

. Results:

Fifteen patients were included in the tremor-dominant subtype, ten patients in the rigid-dominant subtype, and eleven patients in the mixed subtype. Eleven patients were using levodopa, while twenty-five patients had never used any anti-Parkinson’s medication. Ten patients (28%) showed abnormal sympathetic skin responses (SSR). The CPT examination revealed sensory abnormalities in twenty-four patients (67%), with eighteen patients (75%) experiencing sensory hypersensitivity and six patients (25%) experiencing sensory hypoesthesia. Twelve patients (33%) had normal CPT results. Among the patients with abnormal CPT findings, seven cases (29%) involved large myelinated fiber damage, twenty-two cases (92%) involved small myelinated fiber damage, and nineteen cases (79%) involved unmyelinated fiber damage. The rate of sensory abnormalities was 64% (7/11) in the levodopa group and 68% (17/25) in the non-levodopa group, with no statistically significant difference between the two groups. 

. Conclusion:

The incidence of abnormal CPT findings in PD patients was higher than that of abnormal SSR responses, suggesting that nerve fiber damage primarily affects small fiber nerves (SFN).

.


Assuntos
Levodopa , Condução Nervosa , Doença de Parkinson , Humanos , Levodopa/administração & dosagem , Levodopa/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/fisiopatologia , Doença de Parkinson/complicações , Pessoa de Meia-Idade , Feminino , Idoso , Estudos Retrospectivos , Masculino , Condução Nervosa/efeitos dos fármacos , Fibras Nervosas/patologia , Fibras Nervosas/efeitos dos fármacos , Antiparkinsonianos/uso terapêutico , Antiparkinsonianos/efeitos adversos , Nervos Periféricos/patologia
4.
Opt Express ; 31(10): 16484-16494, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37157726

RESUMO

To achieve high sensitivity and uniformity simultaneously in a surface-enhanced Raman scattering (SERS) substrate, this paper presents the preparation of a flexible and transparent three-dimensional (3D) ordered hemispherical array polydimethylsiloxane (PDMS) film. This is achieved by self-assembling a single-layer polystyrene (PS) microsphere array on a silicon substrate. The liquid-liquid interface method is then used to transfer Ag nanoparticles onto the PDMS film, which includes open nanocavity arrays created by etching the PS microsphere array. An open nanocavity assistant soft SERS sample, "Ag@PDMS," is then prepared. For electromagnetic simulation of our sample, we utilized Comsol software. It has been experimentally confirmed that the Ag@PDMS substrate with silver particles of 50 nm in size is capable of achieving the largest localized electromagnetic hot spots in space. The optimal sample, Ag@PDMS, exhibits ultra-high sensitivity towards Rhodamine 6 G (R6G) probe molecules, with a limit of detection (LOD) of 10-15 mol/L, and an enhancement factor (EF) of ∼1012. Additionally, the substrate exhibits a highly uniform signal intensity for probe molecules, with a relative standard deviation (RSD) of approximately 6.86%. Moreover, it is capable of detecting multiple molecules and can perform real detection on non-flat surfaces.

5.
Opt Express ; 31(17): 27304-27311, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37710809

RESUMO

In order to enhance the sensitivity, integration, and practical application capability of Raman detection systems, we propose a multi-channel microfluidic integrated D-shaped optical fiber SERS (Surface-enhanced Raman scattering) probe structure. Firstly, a microfluidic polydimethylsiloxane (PDMS) channel was fabricated using a self-designed multi-channel microfluidic template. Secondly, a uniform layer of silver nanoparticles was deposited on the D-shaped optical fiber using the liquid-liquid interface method. Finally, the D-shaped optical fiber was plasma-bonded to the multi-channel microfluidic channel and a cover glass, resulting in a microfluidic integrated D-shaped optical fiber SERS probe. The prepared sample exhibited excellent detection performance for R6G (rhodamine 6 G) with a detection limit as low as 10-11 mol/L and an enhancement factor of 1.14 × 109. Moreover, the multi-channel configuration enables simultaneous detection of multiple molecules, demonstrating excellent multi-channel multiplexing capability.

6.
Opt Lett ; 48(9): 2377-2380, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37126278

RESUMO

Light-matter interaction is a fascinating topic extensively studied from classical theory, based on Maxwell's equations, to quantum optics. In this study, we introduce a novel, to the best of our knowledge, silver volcano-like fiber-optic probe (sensor 1) for surface-enhanced Raman scattering (SERS). We employ the emerging quasi-normal mode (QNM) method to rigorously calculate the Purcell factor for lossy open system responses, characterized by complex frequencies. This calculation quantifies the modification of the radiation rate from the excited state e to ground state g. Furthermore, we use and extend a quantum mechanical description of the Raman process, based on the Lindblad master equation, to calculate the SERS spectrum for the plasmonic structure. A common and well-established SERS probe, modified by a monolayer silver nanoparticle array, serves as a reference sensor (sensor 2) for quantitatively predicting the SERS performance of sensor 1 using quantum formalism. The predictions show excellent consistency with experimental results. In addition, we employ the FDTD (finite-difference time-domain) solver for a rough estimate of the all-fiber Raman response of both sensors, revealing a reasonable range of SERS performance differences compared to experimental results. This research suggests potential applications in real-time, remote detection of biological species and in vivo diagnostics. Simultaneously, the developed FDTD and quantum optics models pave the way for analyzing the response of emitters near arbitrarily shaped plasmonic structures.

7.
Cerebellum ; 22(5): 973-984, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36028789

RESUMO

BACKGROUND: The cerebellum is involved in regulating motor, affective, and cognitive processes. It is a promising target for transcranial direct current stimulation (tDCS) intervention in stroke. OBJECTIVES: To review the current evidence for cerebellar tDCS (ctDCS) in stroke, its problems, and its future directions. METHODS: We searched the Web of Science, MEDLINE, CINAHL, EMBASE, Cochrane Library, and PubMed databases. Eligible studies were identified after a systematic literature review of the effects of ctDCS in stroke patients. The changes in assessment scale scores and objective indicators after stimulation were reviewed. RESULTS: Eleven studies were included in the systematic review, comprising 169 stroke patients. Current evidence suggests that anode tDCS on the right cerebellar hemisphere does not appear to enhance language processing in stroke patients. Compared with the sham group, stroke patients showed a significant improvement in the verb generation task after cathodal ctDCS stimulation. However, with regard to naming, two studies came to the opposite conclusion. The contralesional anodal ctDCS is expected to improve standing balance but not motor learning in stroke patients. The bipolar bilateral ctDCS protocol to target dentate nuclei (PO10h and PO9h) had a positive effect on standing balance, goal-directed weight shifting, and postural control in stroke patients. CONCLUSIONS: ctDCS appears to improve poststroke language and motor dysfunction (particularly gait). However, the evidence for these results was insufficient, and the quality of the relevant studies was low. ctDCS stimulation parameters and individual factors of participants may affect the therapeutic effect of ctDCS. Researchers need to take a more regulated approach in the future to conduct studies with large sample sizes. Overall, ctDCS remains a promising stroke intervention technique that could be used in the future.


Assuntos
Acidente Vascular Cerebral , Estimulação Transcraniana por Corrente Contínua , Humanos , Estimulação Transcraniana por Corrente Contínua/métodos , Cerebelo/fisiologia , Acidente Vascular Cerebral/terapia , Idioma , Equilíbrio Postural
8.
Neuropediatrics ; 54(2): 139-146, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36473490

RESUMO

BACKGROUND: To explore the neural difference between children with obstructive sleep apnea (OSA) and healthy controls, together with the relation between this difference and clinical severity indicator of children with OSA. METHODS: Twenty-seven children with OSA (7.6 ± 2.5 years, apnea hypopnea index [AHI]: 9.7 ± 5.3 events/h) and 30 healthy controls (7.8 ± 2.6 years, AHI: 1.7 ± 1.2 events/h) were recruited and matched with age, gender, and handedness. All children underwent 3.0 T magnetic resonance imaging of the brain and cognitive testing evaluating. Volumetric segmentation of cortical and subcortical structures and voxel-based morphometry were performed. Pearson's correlation analysis was performed between these features of gray matter volume (GMV) and obstructive apnea index (OAI) among children with OSA. RESULTS: In the comparison of children's Wechsler test scores of full-scale intelligence quotient and verbal intelligence quotient, the OSA group was significantly lower than the control group (p < 0.05). Compared with the control group, the GMV of many brain regions in the OSA group was significantly decreased (p < 0.05). In the correlation analysis of GMV and OAI in OSA group, right inferior frontal gyrus volume was significantly negatively correlated with OAI (r = - 0.49, p = 0.02). CONCLUSION: Children with OSA presented abnormal neural activities in some brain regions and impaired cognitive functions. This finding suggests an association between the OSA and decreased GMV in children.


Assuntos
Substância Cinzenta , Apneia Obstrutiva do Sono , Humanos , Criança , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Apneia Obstrutiva do Sono/diagnóstico por imagem , Apneia Obstrutiva do Sono/patologia , Encéfalo/patologia , Imageamento por Ressonância Magnética , Cognição
9.
J Appl Toxicol ; 43(7): 1064-1072, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36751017

RESUMO

Chlorpromazine (CPZ), a first-generation antipsychotic, is widely used in treating schizophrenia and other psychiatric disorders. However, CPZ is also associated with an increased likelihood of sudden cardiac death, and the underlying mechanisms remain unclear. In our study, we aimed to determine the CPZ-induced changes in some members of the heat shock protein family in rat hearts and further explore the possible mechanisms of CPZ-induced cardiotoxicity. Twenty-four Sprague Dawley rats were randomly divided into three groups (n = 8 per group): control, low dose (33.216 mg/kg) and high dose (94.211 mg/kg). CPZ administration induced hypothermia in rats. Pathological changes, including ischaemia and hypoxia, were observed in rat hearts. Furthermore, the serum levels of cardiac Troponin T (c-TN-T) and brain natriuretic peptide (BNP) were elevated in the CPZ-exposed groups. Meanwhile, the protein and gene expression of HSP70, HSP60, HSP27 and HSP10 significantly differed between the CPZ-exposed and control groups. We conclude that acute CPZ exposure could lead to myocardial injury in rats, in which HSPs might play a crucial role. Further investigations are required to elucidate the underlying mechanisms.


Assuntos
Antipsicóticos , Clorpromazina , Ratos , Animais , Clorpromazina/toxicidade , Cardiotoxicidade , Ratos Sprague-Dawley , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Antipsicóticos/toxicidade
10.
Exp Aging Res ; 49(3): 214-225, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35792710

RESUMO

BACKGROUND: It has been reported that LXR agonist can inhibit Aß generation and alleviate Aß-induced various adverse reactions in vivo and in vitro experiments, but the mechanisms have not been clarified. The study aimed to observe the effect of LXR agonist TO901317 on the cognitive function of AD transgenic mice fed with cholesterol-rich diet (CRD), and to explore the possible mechanism. Methods: 32 male 6-month-old double transgenic AD mice were enrolled and randomly divided into 4 groups: control (normal diet) group, CRD treatment group, TO901317 treatment group and GSK2033 treatment group. After 3 month, Morris water maze was for the changes of spatial exploration and memory ability; ELISA was for detecting the production of Aß42 in the brain; the concentration of total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) in serum were detected by cholesterol enzyme colorimetry; Finally, the expression of LXR-ß, RXR-α, ABCA1, caveolin-1, BACE1 and APP at protein level in the brains was measured by Western blotting. RESULTS: Compared with the control group, the learning, memory ability and spatial exploration ability of the mice were more significantly serious in the CRD group (P<0.05); The contents of TC and LDL in the serum and the production of Aß42 in the brains were significantly increased (P<0.05), but HDL was remarkably decreased (P<0.05); The protein levels of LXR-ß, RXR-α and ABCA1 were also significantly decreased (P<0.05); The expression of caveolin-1, APP and BACE1 were evidently increased (P<0.05). However, after treatment with TO901317, the impaired learning and memory and spatial exploration ability of the mice were significantly improved (P<0.05); The contents of TC and LDL in serum and the production of Aß42 in the brains were significantly decreased (P<0.05), but HLD was increased (P<0.05); The protein levels of LXR-ß, RXR-α, ABCA1were all significantly increased (P<0.05), while, the expression of caveolin-1, APP and BACE1 were all significantly decreased (P<0.05). All the changes were reversed by GSK2033 (P<0.05). CONCLUSIONS: TO901317 attenuated the more serious impairment of spatial exploration, learning and memory in transgenic AD mice induced by CRD, and the mechanism may be that TO901317 could activate the LXR-ß/RXR-α/ABCA1 transmembrane transport system, promote the cholesterol efflux, and decreased caveolin-1, APP and BACE1, further reduce Aß42 in the brains.


Assuntos
Secretases da Proteína Precursora do Amiloide , Receptores Nucleares Órfãos , Animais , Humanos , Masculino , Camundongos , Envelhecimento , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Transportador 1 de Cassete de Ligação de ATP , Caveolina 1/metabolismo , Colesterol , Cognição , Dieta , Receptores X do Fígado/metabolismo , Microdomínios da Membrana/metabolismo , Camundongos Transgênicos , Receptores Nucleares Órfãos/metabolismo , Transporte Proteico , Receptor X Retinoide alfa/metabolismo
11.
Opt Express ; 30(18): 32660-32669, 2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36242322

RESUMO

Surface plasmon lithography breaks through the diffraction limit with surface plasmon effect and achieves high-resolution imaging below sub-wavelengths. The dynamic detection and control of the working distance between the mask and the substrate is particularly important for the quality of the lithography samples. In this paper, the mask-substrate gap sensing mechanism is analyzed, and a mask-substrate gap absolute distance measurement model is established based on the principle of white light interference. We design a Fizeau interferometer demodulation system based on a hardware optical correlation method, and focus on analyzing the influence of the sub-nanometer surface profile of the optical wedge on the resolution. Finally, we propose a data processing method for extracting the dynamic gap value by SSA (singular spectrum analysis). The experimental results show that the system shows high performance with a gap detection range of 3.0∼6.0 µm, the stability of ±0.12 nm, and the resolution of better than 0.30 nm.

12.
Future Oncol ; 18(6): 669-677, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35080187

RESUMO

Aim: To investigate the efficacy, safety and optimal dosage of bevacizumab in non-squamous, non-small-cell lung cancer (NSCLC) patients with malignant pleural effusion (MPE). Methods: 20 patients were enrolled and received intrapleural injection of bevacizumab (group A: 2.5 mg/kg d1, d8; group B: 5 mg/kg d1, d8; group C: 7.5 mg/kg d1, d8). Results: The objective response rate (ORR) of MPE was 50%. The median progression-free survival (PFS) of MPE was 7.0 months (95% CI 4.9-9.2). The ORR and PFS of MPE from group B were better than those of group A and group C. The most common adverse events (AEs) were hypertension (15%) and anemia (15%). Conclusion: Bevacizumab has certain efficacy in non-squamous NSCLC patients with MPE. Clinical Trial Registration: NCT02942043 (ClinicalTrials.gov).


Assuntos
Inibidores da Angiogênese/administração & dosagem , Antineoplásicos Imunológicos/administração & dosagem , Bevacizumab/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/complicações , Neoplasias Pulmonares/complicações , Derrame Pleural Maligno/tratamento farmacológico , Idoso , Inibidores da Angiogênese/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Bevacizumab/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Derrame Pleural Maligno/etiologia , Intervalo Livre de Progressão , Estudos Prospectivos
13.
Genomics ; 113(2): 490-496, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33385494

RESUMO

Steroid-induced necrosis of femoral head (SINFH) is a femoral head necrotic disease caused by prolonged use of hormones. The detailed pathogenesis has not been fully demonstrated. In this study, we employed the bioinformatics approach to probe the roles of SINFH inhibitors. Core dysfunction modules related to SINFH was obtained. Meanwhile, GO and KEGG analysis of genes in dysfunction modules are carried out. Furthermore, the pivot prediction analysis of dysfunction modules related to ncRNA and transcription factor (TF) has been performed. The functions of the enriched modules were focused on multiple perspectives, including circulation, gland development, bone development and reconstruction, calcium production, and fatty acid metabolism regulation. The ncRNAs and TFs analysis showed that miR-322-5p, miR-124-3p, miR-125a-3p, and Ctnnb1 were important members of SINFH dysfunction. Drug targets suggested that Zinc and adenosine monophosphate may have an impact on SINFH dysfunction. SINFH was closely related to bone development and reconstruction.


Assuntos
Necrose da Cabeça do Fêmur/genética , Farmacologia em Rede , RNA não Traduzido/genética , Fatores de Transcrição/genética , Animais , Anti-Inflamatórios/uso terapêutico , Necrose da Cabeça do Fêmur/tratamento farmacológico , Necrose da Cabeça do Fêmur/etiologia , Necrose da Cabeça do Fêmur/metabolismo , Humanos , RNA não Traduzido/metabolismo , Ratos , Esteroides/toxicidade , Fatores de Transcrição/metabolismo
14.
BMC Plant Biol ; 21(1): 85, 2021 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-33563229

RESUMO

BACKGROUND: Rice plants suffer from the rising temperature which is becoming more and more prominent. Mining heat-resistant genes and applying them to rice breeding is a feasible and effective way to solve the problem. RESULT: Three main biomass traits, including shoot length, dry weight, and fresh weight, changed after abnormally high-temperature treatment in the rice seedling stage of a recombinant inbred lines and the natural indica germplasm population. Based on a comparison of the results of linkage analysis and genome-wide association analysis, two loci with lengths of 57 kb and 69 kb in qDW7 and qFW6, respectively, were associated with the rice response to abnormally high temperatures at the seedling stage. Meanwhile, based on integrated transcriptome analysis, some genes are considered as important candidate genes. Combining with known genes and analysis of homologous genes, it was found that there are eight genes in candidate intervals that need to be focused on in subsequent research. CONCLUSIONS: The results indicated several relevant loci, which would help researchers to further discover beneficial heat-resistant genes that can be applied to rice heat-resistant breeding.


Assuntos
Genes de Plantas , Temperatura Alta , Oryza/crescimento & desenvolvimento , Oryza/genética , Plântula/crescimento & desenvolvimento , Plântula/genética , Estresse Fisiológico/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ligação Genética , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo
15.
J Pharmacol Exp Ther ; 377(1): 121-132, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33514607

RESUMO

We have created a novel glutathione S-transferase π1 (gstp1) knockout (KO) zebrafish model and used it for comparative analyses of redox homeostasis and response to drugs that cause endoplasmic reticulum (ER) stress and induce the unfolded protein response (UPR). Under basal conditions, gstp1 KO larvae had higher expression of antioxidant nuclear factor erythroid 2-related factor 2 (Nrf2) accompanied by a more reduced larval environment and a status consistent with reductive stress. Compared with wild type, various UPR markers were decreased in KO larvae, but treatment with drugs that induce ER stress caused greater toxicities and increased expression of Nrf2 and UPR markers in KO. Tunicamycin and 02-{2,4-dinitro-5-[4-(N-methylamino)benzoyloxy]phenyl}1-(N,N-dimethylamino)diazen-1-ium-1,2-diolate (PABA/nitric oxide) activated inositol-requiring protein-1/X-box binding protein 1 pathways, whereas thapsigargin caused greater activation of protein kinase-like ER kinase/activating transcription factor 4/CHOP pathways. These results suggest that this teleost model is useful for predicting how GSTP regulates organismal management of oxidative/reductive stress and is a determinant of response to drug-induced ER stress and the UPR. SIGNIFICANCE STATEMENT: A new zebrafish model has been created to study the importance of glutathione S-transferase π1 in development, redox homeostasis, and response to drugs that enact cytotoxicity through endoplasmic reticulum stress and induction of the unfolded protein response.


Assuntos
Glutationa S-Transferase pi/metabolismo , Resposta a Proteínas não Dobradas , Ácido 4-Aminobenzoico/toxicidade , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glutationa S-Transferase pi/genética , Homeostase , Larva/efeitos dos fármacos , Larva/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Óxido Nítrico/toxicidade , Oxidantes/toxicidade , Oxirredução , Transcriptoma , Tunicamicina/toxicidade , Peixe-Zebra , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
16.
Opt Lett ; 46(17): 4300-4303, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34469999

RESUMO

A Raman sensor based on a cavity-enhanced Ag nanoparticle (AgNP) decorated tapered fiber is proposed. Its Raman enhancements are mainly caused by the localized surface plasmon resonance effect of AgNPs decorated on the tapered optical fiber surface and the further reflective laser excitation induced by the capillary-based reflective cavity. We theoretically investigate the backward Stokes power conversion efficiency and cavity enhancement factor of the sensor. The calculated relationship between the cavity enhancement factor ξ and distance L from the tip to reflective rod is also discussed. Subsequently, the proving experiments were carried out for a tapered fiber surface-enhanced Raman scattering (SERS) probe and cavity-enhanced metal decorated tapered fiber Raman sensors. The analytical enhancement factor is 5.51×104 for the tapered fiber SERS probe. Moreover, the predicted curves of the theoretical model are close to the experimental values. This Letter provides a possible way to rigorously quantify the complete coupling efficiency for tapered fiber SERS probes, as well as cavity enhancement factors of cavity-enhanced Raman sensors.

17.
Biochem Biophys Res Commun ; 526(4): 1021-1027, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32317184

RESUMO

In the application of human umbilical cord-derived mesenchymal stem cells (UC-MSCs) as clinical therapeutics, long term cells ex vivo expansion results in decline in their function. It has been widely concerned that cellular senescence is associated with UC-MSCs immunomodulatory ability. In this study, we evaluated the effects of consecutive passages on cellular senescence and the immunomodulatory abilities of UC-MSCs. Long term-cultured UC-MSCs showed decreased proliferation, senescence phenotypes and impaired immunosuppressive effects on PHA induced peripheral blood mononuclear cell (PBMC) proliferation. We found that Nrf2, a transcription factor that responds to oxidative stress, that showed decreased expression in long term-cultured UC-MSCs, and the further knock-down of Nrf2 in UC-MSCs induced premature senescence, decreased proliferation ability and immunosuppressive abilities. Furthermore, the protein expression of IDO-1 were decreased in response to the downregulation of Nrf2 in UC-MSCs, suggesting that Nrf2 regulates the immunosuppressive properties of UC-MSCs via Nrf2-mediated IDO-1 expression. In conclusion, our results demonstrate that Nrf2 plays a key role in the regulation of the immunosuppressive properties of UC-MSCs, and we suggest that these findings might provide a strategy to enhance the functionality of UC-MSCs for use in therapeutic applications.


Assuntos
Senescência Celular , Terapia de Imunossupressão , Células-Tronco Mesenquimais/citologia , Fator 2 Relacionado a NF-E2/metabolismo , Cordão Umbilical/citologia , Técnicas de Cultura de Células , Proliferação de Células , Células Cultivadas , Regulação para Baixo , Técnicas de Silenciamento de Genes , Humanos , Fenótipo
18.
Opt Express ; 28(21): 31993-32001, 2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33115162

RESUMO

Using a self-encapsulation technology, we prepared a metal film-coupled nanoisland system (FCN), that is, Ag and Al2O3 film-coupled Ag nanoislands (AgNIs/Al2O3/Ag) composite SERS (surface-enhanced Raman scattering) substrate, through the anti-wetting of Ag film on the surface of Al film. The thickness of the Al2O3 film can be controlled within the range of 4 nm to 22 nm by tuning the annealing temperature. Three important properties were investigated. Firstly, the structure shows an excellent near-field and far-field enhancement using COMSOL Multiphysics simulation. Secondly, the experimental SERS analytical enhancement factor (AEF) of the AgNIs/Al2O3/Ag substrate can reach 3.9 × 108, two orders of magnitude larger than that of bare AgNIs. Thirdly, after exposed in air for 90 days, it can keep 55% enhancement capability, while the bare AgNIs can keep 16%.

19.
J Appl Toxicol ; 40(8): 1153-1161, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32162354

RESUMO

Early diagnosis of cantharidin-induced myocardial injury is the key to reduce the fatality rate in clinical practice. The purpose of the present study was to explore biomarkers that can be used for the prediction and diagnosis of cantharidin-induced myocardial injury. Of 65 male Sprague-Dawley rats weighing 200-230 g, 25 rats were divided into five groups according to the administration dose of cantharidin (0, 1.34, 2.67, 4 and 5.34 mg/kg; n = 5 per group) and the other 40 rats were treated with 2.67 mg/kg cantharidin and divided into nine groups according to the administration time (0, 1, 2, 4, 6, 8, 12, 24, 48 and 72 hours; n = 4 per group). Pathological changes of hypoxia, necrosis and inflammation were confirmed in heart samples that were exposed to cantharidin by hematoxylin-eosin staining and overall scores of pathological changes among heart samples in cantharidin exposure groups showed an increasing trend compared with in the control group. Coexpression of vascular endothelial growth factor (VEGF), hypoxia inducible factor-1α (HIF-1α) and caspase9 was shown in the myocardium by immunofluorescence staining. Western blotting results showed that expression of VEGF, HIF-1α and caspase9 in cantharidin-treated rat hearts showed an increasing trend compared with in the control group. Results of enzyme-linked immunosorbent assay suggested that plasma levels of troponin T (TN-T), VEGF and HIF-1α were elevated at different intervals after cantharidin administration, and VEGF and HIF-1α had a significant linear relationship with TN-T that was verified by multiple linear regression analysis. Preliminary results serve to illustrate that TN-T, VEGF and HIF-1α might be valuable molecular markers in cantharidin-induced myocardial injury and that diagnostic accuracy needs to be studied further.


Assuntos
Biomarcadores/sangue , Cantaridina/toxicidade , Cardiomiopatias/induzido quimicamente , Cardiotoxicidade/fisiopatologia , Troponina T/efeitos dos fármacos , Fatores de Crescimento do Endotélio Vascular/efeitos dos fármacos , Animais , Cardiomiopatias/fisiopatologia , Relação Dose-Resposta a Droga , Hipóxia/induzido quimicamente , Hipóxia/fisiopatologia , Inflamação/induzido quimicamente , Inflamação/fisiopatologia , Masculino , Necrose/induzido quimicamente , Necrose/fisiopatologia , Valor Preditivo dos Testes , Ratos , Ratos Sprague-Dawley
20.
Zhongguo Zhong Yao Za Zhi ; 45(21): 5226-5231, 2020 Nov.
Artigo em Zh | MEDLINE | ID: mdl-33350239

RESUMO

This work was launched to study on the chemical constituents from Euphorbia thymifolia. Thirteen compounds were isolated from the 95% ethanol extract of the aerial parts of E. thymifolia by column chromatographies on silica gel, Sephadex LH-20, MCI, and ODS, and preparative HPLC, including two thymol derivatives(1-2), four alkaloids(3-6), five isocoumarins(7-11), together with two ellagic acids(12-13). All the compounds are listed as follows:(Z)-8,9-dehydro-9,10-diisobutyryloxythymol(1), 8-hydro-xy-9,10-diisobutyryloxythymol(2), N-(N-benzoyl-L-phenylalanyl)-L-phenylalanol(3), aurantiamide acetate(4), 1-carboethoxy-ß-carboline(5), isoechinulin A(6), ethyl brevifolincarboxylate(7), euphorhirtin B(8), 4,5-didehydro chebulic acid triethyl ester(9), euphorhirtin G(10), pomegranatate(11), 3,3',4'-tri-O-methylellagic acid(12), 3,3'-di-O-methylellagic acid(13). Compound 1 is a new compound. Except for compound 4, the others were isolated from this plant for the first time. All the compounds were screened for anti-neuroinflammatory activity in vitro, and compounds 1-3 and 7 showed significant activity with IC_(50) values of 0.19,12.93,7.29,25.4 µmol·L~(-1).


Assuntos
Euphorbia , Cromatografia Líquida de Alta Pressão
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